As a ferroelectric film applied to semiconductor devices (ferroelectric memories (FeRAM), for example), ferroelectric films having a layered perovskite structure (BiLaTiO-based, BiTiO-based, and SrBiTaO-based ferroelectric films, for example) have been proposed. These ferroelectric films having a layered perovskite structure are generally formed by allowing crystals to grow from an amorphous state.
In the case of forming a ferroelectric film having a layered perovskite structure using this formation method, the crystal growth rate in the c-axis direction becomes lower than those in the a-axis direction and the b-axis direction due to the crystal structure of the ferroelectric film. Specifically crystals tend to grow in the a-axis direction and the b-axis direction Therefore, the ferroelectric film having a layered perovskite structure formed by using the above method has a rough surface morphology. Specifically, openings (holes or grooves, for example) are formed between crystals in the resulting ferroelectric film.